mlocate

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mlocate is a merging locate and database package. "Merging" means updatedb reuses the existing database to avoid re-reading most of the file system. This makes the database update faster and does not tax the system caches.[1] mlocate can index several file systems including network file systems for network shares. This package is essential when attempting to quickly find documents in a terminal.

Installation

USE flags

USE flags for sys-apps/mlocate Merging locate is an utility to index and quickly search for files

nls Add Native Language Support (using gettext - GNU locale utilities) global
selinux !!internal use only!! Security Enhanced Linux support, this must be set by the selinux profile or breakage will occur global

Emerge

Emerge sys-apps/mlocate via:

root #emerge --ask sys-apps/mlocate

Once installed mlocate can be invoked with the locate command.

Configuration

Files

To have network file systems included when mlocate's index is populated edit the pruning of the file system variable (PRUNEFS) in the /etc/updatedb.conf file. Remove the nfs, NFS, and nfs4, nfsd entries:

FILE /etc/updatedb.confInclude network file systems example
# This file sets variables that are used by updatedb.
# For more info, see the updatedb.conf(5) manpage.

# Filesystems that are pruned from updatedb database
PRUNEFS="afs anon_inodefs auto autofs bdev binfmt binfmt_misc cgroup cifs coda configfs cramfs cpuset debugfs devfs devpts devtmpfs ecryptfs eventpollfs exofs futexfs ftpfs fuse fusectl gfs gfs2 hostfs hugetlbfs inotifyfs iso9660 jffs2 lustre misc mqueue ncpfs nnpfs ocfs ocfs2 pipefs proc ramfs rpc_pipefs securityfs selinuxfs sfs shfs smbfs sockfs spufs sshfs subfs supermount sysfs tmpfs ubifs udf usbfs vboxsf vperfctrfs"

# Paths which are pruned from updatedb database
PRUNEPATHS="/tmp /var/tmp /var/cache /var/lock /var/run /var/spool"

# Folder names that are pruned from updatedb database
PRUNENAMES=".git .hg .svn CVS"

# Skip bind mounts.
PRUNE_BIND_MOUNTS="yes"

Usage

Initial database indexing

Upon installation, the updatedb command will automatically be added as a scheduled cron job. To index the files immediately run:

root #updatedb

Searching can be performed as soon as this step is complete.

Invocation

See more options from the command-line by asking for help:

root #locate --help
Usage: locate [OPTION]... [PATTERN]...
Search for entries in a mlocate database.

  -A, --all              only print entries that match all patterns
  -b, --basename         match only the base name of path names
  -c, --count            only print number of found entries
  -d, --database DBPATH  use DBPATH instead of default database (which is
                         /var/lib/mlocate/mlocate.db)
  -e, --existing         only print entries for currently existing files
  -L, --follow           follow trailing symbolic links when checking file
                         existence (default)
  -h, --help             print this help
  -i, --ignore-case      ignore case distinctions when matching patterns
  -l, --limit, -n LIMIT  limit output (or counting) to LIMIT entries
  -m, --mmap             ignored, for backward compatibility
  -P, --nofollow, -H     don't follow trailing symbolic links when checking file
                         existence
  -0, --null             separate entries with NUL on output
  -S, --statistics       don't search for entries, print statistics about each
                         used database
  -q, --quiet            report no error messages about reading databases
  -r, --regexp REGEXP    search for basic regexp REGEXP instead of patterns
      --regex            patterns are extended regexps
  -s, --stdio            ignored, for backward compatibility
  -V, --version          print version information
  -w, --wholename        match whole path name (default)

Report bugs to mitr@redhat.com.

To find all Firefox executables:

root #locate firefox | grep bin

Troubleshooting

Cannot find a file

When having trouble finding a newly installed file, be sure the database has been manually rebuilt before the search. The default cron job will index on a daily basis, however the chances of it running directly after new files have been added to the system is slim.

More information concerning the default cron job can be found in the /etc/cron.daily/mlocate file.

See also

  • find - A search command included in nearly all Linux systems.

References

  1. https://pagure.io/mlocate